[ComradeTaco]

Okay, my bachelors was in civil engineering and I have worked in construction and engineering for just over two years now.

Most public projects today have generous structured incentives that are given to companies for meeting goals for time and budget. We work to these incentives.

Keep in mind that often you cannot be aware of the things that will go wrong until you actually do them. This happens in software development quite a bit.

I am not aware of any extensive private tunnel construction that has occurred without public financing inside of the U.S.

So here are the drawbacks to Musk's plan:

1. He may prioritize speed over safety, either unintentionally causing loss of life or limb because of construction practices or geotechnically destablize the foundations of the buildings and infrastructure that he's traveling under.

2. I firmly believe that it's going to cost far, far more than 1 billion. That leaves the chance of a big hole in the ground that may eventually fill with water.

[jandrese]

If he hits the $1 billion target this will be the civil engineering project of the century. It's hard to overstate just how optimistic that figure is compared to literally every other mass transit project worldwide.

The craziest part is that there is already a much cheaper and not that much slower option to get to the airport. This project seems rather Quixotic.

[rohit2412]

Why is it so unrealistic? For example, this line in Mumbai metro ( https://en.m.wikipedia.org/wiki/Line_3_(Mumbai_Metro) ), with 34 km of big tunnels and 27 stations is supposed to cost 3.4 billion. Surely, Chicago's 25-30 km line with just two stations (one sort of half built already) and smaller tunnels won't cost so much.

[jandrese]

Two things. 1 is that they're planning to use a lot of cut and cover which is a lot cheaper but more disruptive. 2 is that the project isn't complete yet so those final cost figures are still fiction.

[rohit2412]

No, only the stations are cut and cover. They have ordered 17 tbm for the tunnels.

About the cost estimate, I don't have any other completely underground metro line in a developing country to compare. But Is it the labor costs in developed countries?